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Constant Power Control Of Dfig Wind Turbines With Supercapacitor Energy Storage, Liyan Qu, Wei Qiao 2011 University of Nebraska-Lincoln

Constant Power Control Of Dfig Wind Turbines With Supercapacitor Energy Storage, Liyan Qu, Wei Qiao

Department of Electrical and Computer Engineering: Faculty Publications

With the increasing penetration of wind power into electric power grids, energy storage devices will be required to dynamically match the intermittency of wind energy. This paper proposes a novel two-layer constant power control scheme for a wind farm equipped with doubly fed induction generator (DFIG) wind turbines. Each DFIG wind turbine is equipped with a super-capacitor energy storage system (ESS) and is controlled by the low-layer wind turbine generator (WTG) controllers and coordinated by a high-layer wind farm supervisory controller (WFSC). The WFSC generates the active power references for the low-layer WTG controllers according to the active power demand …


An Extended Cavity Method To Analyze Slot Coupling Between Printed Circuit Board Cavities, Gang Feng, Jun Fan 2011 Missouri University of Science and Technology

An Extended Cavity Method To Analyze Slot Coupling Between Printed Circuit Board Cavities, Gang Feng, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In high-speed multilayer printed circuit boards, gaps are commonly used in planes, where different areas are utilized for different logic levels or where noise isolation from one area to another is necessary. However, these gap structures could present serious signal integrity and electromagnetic interference issues. in this paper, an extended cavity method is developed to characterize noise coupling caused by slots or gaps in the middle plane of a three-plane structure. According to the equivalence principle, the entire structure can be divided into two plane pairs without any slot in the middle plane, and then, equivalent magnetic currents are needed …


Underwater Communication Via Particle Velocity Channels : Principles, Channel Models, And System Design, Huaihai Guo 2011 New Jersey Institute of Technology

Underwater Communication Via Particle Velocity Channels : Principles, Channel Models, And System Design, Huaihai Guo

Dissertations

A vector sensor is capable of measuring important non-scalar components of the acoustic field such as the particle velocity, which cannot be obtained by a single scalar pressure sensor. In the past few decades, extensive research has been conducted on the theory and design of vector sensors. On the other hand, underwater acoustic communication systems have been relying on scalar sensors only, which measure the pressure of the acoustic field. By taking advantage of the vector components of the acoustic field, such as the particle velocity, the vector sensor can be used for detecting the transmitted data. In this dissertation, …


Design Of Single-Carrier Frequency Domain Equalization (Sc-Fde) With Transmit Diversity For Wireless And Optical Communications, Kodzovi Acolatse 2011 New Jersey Institute of Technology

Design Of Single-Carrier Frequency Domain Equalization (Sc-Fde) With Transmit Diversity For Wireless And Optical Communications, Kodzovi Acolatse

Dissertations

As the demand of wireless service is rising, there is a need to transmit high-speed packets over the wireless communication channel. Broadband data transmission over wireless channels commonly faces the challenges of multipath fading channels, which are both time and frequency selective. There is then a need to design transmission techniques that can combat the adverse effects of the channel, and enable reliable high data rate wireless services. Orthogonal frequency division multiplexing (OFDM) has become widely accepted primarily because of its robustness against frequency selective fading channels, but it suffers a number of drawbacks such as high peak-to-average power ratio …


Tin/Hfo2/Sio2/Si Gate Stacks Reliability : Contribution Of Hfo2 And Interfacial Sio2 Layer, Nilufa Rahim 2011 New Jersey Institute of Technology

Tin/Hfo2/Sio2/Si Gate Stacks Reliability : Contribution Of Hfo2 And Interfacial Sio2 Layer, Nilufa Rahim

Dissertations

Hafnium Oxide based gate stacks are considered to be the potential candidates to replace SiO2 in complementary metal-oxide-semiconductor (CMOS), as they reduce the gate leakage by over 100 times while keeping the device performance intact. Even though considerable performance improvement has been achieved, reliability of high-κ devices for the next generation of transistors (45nm and beyond) which has an interfacial layer (IL: typically SiO2) between high-κ and the substrate, needs to be investigated. To understand the breakdown mechanism of high-κ/SiO2 gate stack completely, it is important to study this multi-layer structure extensively. For example, (i) the …


Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese 2011 New Jersey Institute of Technology

Distributed Synchronization Algorithms For Wireless Sensor Networks, Nicola Varanese

Dissertations

The ability to distribute time and frequency among a large population of interacting agents is of interest for diverse disciplines, inasmuch as it enables to carry out complex cooperative tasks. In a wireless sensor network (WSN), time/frequency synchronization allows the implementation of distributed signal processing and coding techniques, and the realization of coordinated access to the shared wireless medium. Large multi-hop WSN's constitute a new regime for network synchronization, as they call for the development of scalable, fully distributed synchronization algorithms. While most of previous research focused on synchronization at the application layer, this thesis considers synchronization at the lowest …


Model Reference Control For Ultra-High Precision Positioning Systems, Lan Yu 2011 New Jersey Institute of Technology

Model Reference Control For Ultra-High Precision Positioning Systems, Lan Yu

Dissertations

Due to the increasing demands of high-density semiconductors, molecular biology, optoelectronics, and MEMS/NEMS in the past decades, control of ultra-high precision positioning using piezoelectricity has become an important area because of its high displacement resolution, wide bandwidth, low power consumption, and potential low cost. However, the relatively small displacement range limits its application. This work proposed a practical ultra-high precision piezoelectric positioning system with a complementary high displacement range actuation technology. Solenoids are low cost, high speed electromagnetic actuators which are commonly used in on-off mode only because of the inherent high nonlinear force-stroke characteristics and unipolar forces (push/pull) generated …


Novel Bioelectrical Measurement Using A Digital Biopotential Monode, Mark Nolan, Edward Burke, Eugene Coyle 2011 Technological University Dublin

Novel Bioelectrical Measurement Using A Digital Biopotential Monode, Mark Nolan, Edward Burke, Eugene Coyle

Conference Papers

In conventional biopotential recording, two or more electrodes are placed on the body. A unipolar lead records the time-varying electrical potential at a single point (relative to a reference potential) via one signal electrode. A bipolar lead records the time-varying potential difference between two points via two signal electrodes. In each case, the signal electrodes are connected to high impedance amplifier inputs, while an additional electrode provides a low-impedance path between the amplifier and human subject. Bipolar leads are usually preferred since interference appearing at both signal electrodes can be eliminated using an instrumentation amplifier with high CMRR. A drawback …


A Mask-Based Enhancement Method For Historical Documents, Elisa H. Barney Smith, Jerôme Darbon, Laurence Likforman-Sulem 2011 Boise State University

A Mask-Based Enhancement Method For Historical Documents, Elisa H. Barney Smith, Jerôme Darbon, Laurence Likforman-Sulem

Electrical and Computer Engineering Faculty Publications and Presentations

This paper proposes a novel method for document enhancement. The method is based on the combination of two state-of-the-art filters through the construction of a mask. The mask is applied to a TV (Total Variation) -regularized image where background noise has been reduced. The masked image is then filtered by NLmeans (Non-Local Means) which reduces the noise in the text areas located by the mask. The document images to be enhanced are real historical documents from several periods which include several defects in their background. These defects result from scanning, paper aging and bleed-through. We observe the improvement of this …


Characterizing Challenged Minnesota Ballots, George Nagy, Daniel Lopresti, Elisa H. Barney Smith, Ziyan Wu 2011 Rensselaer Polytechnic Institute

Characterizing Challenged Minnesota Ballots, George Nagy, Daniel Lopresti, Elisa H. Barney Smith, Ziyan Wu

Electrical and Computer Engineering Faculty Publications and Presentations

Photocopies of the ballots challenged in the 2008 Minnesota elections, which constitute a public record, were scanned on a high-speed scanner and made available on a public radio website. The PDF files were downloaded, converted to TIF images, and posted on the PERFECT website. Based on a review of relevant image-processing aspects of paper-based election machinery and on additional statistics and observations on the posted sample data, robust tools were developed for determining the underlying grid of the targets on these ballots regardless of skew, clipping, and other degradations caused by high-speed copying and digitization. The accuracy and robustness of …


Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle 2011 Technological University Dublin

Intelligibility Of Electrolarynx Speech Using A Novel Hands-Free Actuator, Brian Madden, Mark Nolan, Ted Burke, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx provides quasi-periodic acoustic excitation of the vocal tract. In most electrolarynxes, mechanical vibrations are produced by a linear electromechanical actuator, the armature of which percusses against a metal or plastic plate at a frequency within the range of glottal excitation. In this paper, the intelligibility of speech produced using a novel hands-free actuator is compared to speech produced using a conventional electrolarynx. Two able-bodied speakers (one male, one female) performed a closed response test containing 28 monosyllabic words, once using a conventional electrolarynx and a second time using the novel design. The resulting audio recordings …


Detecting Software Attacks By Monitoring Electric Power Consumption Patterns, Grant A. Jacoby, Nathaniel J. Davis IV, Randolph C. Marchany 2011 Air Force Institute of Technology

Detecting Software Attacks By Monitoring Electric Power Consumption Patterns, Grant A. Jacoby, Nathaniel J. Davis Iv, Randolph C. Marchany

AFIT Patents

Software attacks such as worms and viruses are detected in an electronic device by monitoring power consumption patterns. In a first embodiment, software attacks are detected by an increase in power consumption. The increased power consumption can be caused by increased network traffic, or by increased activity in the microprocessor. Monitoring power consumption is particularly effective for detecting DOS/flooding attacks when the electronic device is in an idle state. In a second embodiment, a power consumption signal is converted to the frequency domain (e.g., by fast Fourier transform). The highest amplitude frequencies are identified. Specific software attacks produce characteristic frequencies …


Top Transmission Grating Gan Led Simulations For Light Extraction Improvement, Simeon Trieu, Xiaomin Jin, Ashton Ellaboudy, Bei Zhang, Xiang-Ning Kang, Guo-Yi Zhang, Xiong Chang, Wei Wei, Sun Yong Jian, Fu Xing Xing 2011 California Polytechnic State University - San Luis Obispo

Top Transmission Grating Gan Led Simulations For Light Extraction Improvement, Simeon Trieu, Xiaomin Jin, Ashton Ellaboudy, Bei Zhang, Xiang-Ning Kang, Guo-Yi Zhang, Xiong Chang, Wei Wei, Sun Yong Jian, Fu Xing Xing

Electrical Engineering

We study the top transmission grating’s improvement on GaN LED light extraction efficiency. We use the finite difference time domain (FDTD) method, a computational electromagnetic solution to Maxwell’s equations, to measure light extraction efficiency improvements of the various grating structures. Also, since FDTD can freely define materials for any layer or shape, we choose three particular materials to represent our transmission grating: 1) nonlossy p-GaN, 2) lossy indium tin oxide (ITO), and 3) non-lossy ITO (α=0). We define a regular spacing between unit cells in a crystal lattice arrangement by employing the following three parameters: grating cell period (Α), grating …


Descreening Of Color Halftone Images In The Frequency Domain, C. J. Stanger, Thanh Tran, Elisa H. Barney Smith 2011 Boise State University

Descreening Of Color Halftone Images In The Frequency Domain, C. J. Stanger, Thanh Tran, Elisa H. Barney Smith

Electrical and Computer Engineering Faculty Publications and Presentations

Scanning a halftone image introduces halftone artifacts, known as Moiré patterns, which significantly degrade the image quality. Printers that use amplitude modulation (AM) screening for halftone printing position dots in a periodic pattern. Therefore, frequencies relating halftoning are easily identifiable in the frequency domain. This paper proposes a method for descreening scanned color halftone images using a custom band reject filter designed to isolate and remove only the frequencies related to halftoning while leaving image edges sharp without image segmentation or edge detection. To enable hardware acceleration, the image is processed in small overlapped windows. The windows are filtered individually …


A Correlation-Based Method To Detect Weak Dependence, Yabing Luo 2011 Brigham Young University - Provo

A Correlation-Based Method To Detect Weak Dependence, Yabing Luo

Theses and Dissertations

The focus of this thesis is an investigation of ways to detect weak dependence between two random variables X and Y. Our approach is to design tests for correlation rather than testing for dependence directly, since X and Y are not independent if they are not uncorrelated. We examined the magnified Pearson correlation after the Box-Cox transformation to determine whether X and Y are dependent. The results indicated that our approach not only has the potential to detect and evaluate the weak dependence cases that have previously been intractable, but also is conceptually simple and easy to implement.


Transparent Patch Antenna On A-Si Thin Film Glass Solar Module, Maria Roo Ons, S. Shynu, Max Ammann, Sarah McCormack, Brian Norton 2011 Technological University Dublin

Transparent Patch Antenna On A-Si Thin Film Glass Solar Module, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton

Articles

An optically transparent microstrip patch mounted on the surface of a commercially available solar module is proposed. The patch comprises a thin sheet of clear polyester with a conductive coating. The amorphous silicon solar cells in the module are used as both photovoltaic generator and antenna ground plane. The proposed structure provides a peak gain of 3.96 dBi in the 3.4-3.8 GHz range without significantly compromising the light transmission in the module. A comparison between copper and transparent conductors is made in terms of antenna and solar performance. The proposed technique is considerably simpler that previous integration approaches.


Electro-Luminescent Display With Power Line Voltage Compensation, Michael E. Miller, Michael J. Murdoch, John W. Harmer 2011 Air Force Institute of Technology

Electro-Luminescent Display With Power Line Voltage Compensation, Michael E. Miller, Michael J. Murdoch, John W. Harmer

AFIT Patents

An active matrix electro-luminescent display system, comprising: a display composed of an array of regions of light-emitting elements, pixel driving circuits for independently controlling the current to each light-emitting element, one or more display drivers for receiving an input image signal for data to drive the pixel driving circuits and generating a converted image signal for driving the light emitting elements in each region of the display through signals provided through data lines and select lines, wherein the one or more display drivers sequentially receive the input image signal for driving the light emitting elements within each region of the …


Electron Hop Funnel Measurements And Comparison With The Lorentz-2e Simulation, Charles Lester, Jim Browning, Lael Matthews 2011 Boise State University

Electron Hop Funnel Measurements And Comparison With The Lorentz-2e Simulation, Charles Lester, Jim Browning, Lael Matthews

Electrical and Computer Engineering Faculty Publications and Presentations

Electron hop funnels have been fabricated using a Low Temperature Co-Fired Ceramic (LTCC). Measurements of the hop funnel I-V curve and electron energy distribution have been made using gated field emitters as the electron source. The charged particle simulation Lorentz 2E has been used to model the hop funnel charging and to predict the I-V and energy characteristics. The results of this comparison indicate that the simulation can be used to design hop funnel structures for use in various applications.


Nano-Particle/Quantum Dot Based Optical Dode, Dennis R. Alexander, John C. Bruce, Craig A. Zuhlke, Brandon E. Koch, Jitender S. Deogun, Haitham S. Hamza 2011 Lincoln, Nebraska

Nano-Particle/Quantum Dot Based Optical Dode, Dennis R. Alexander, John C. Bruce, Craig A. Zuhlke, Brandon E. Koch, Jitender S. Deogun, Haitham S. Hamza

Department of Electrical and Computer Engineering: Faculty Publications

A particle based optical diode having at least two cavities or at least two regions of a single cavity, wherein the regions contain different types of particles.


Augmented Control Of A Hands-Free Electrolarynx, Brian Madden, James Condron, Eugene Coyle 2011 Technological University Dublin

Augmented Control Of A Hands-Free Electrolarynx, Brian Madden, James Condron, Eugene Coyle

Conference Papers

During voiced speech, the larynx acts as the sound source, providing a quasi-periodic excitation of the vocal tract. Following a total laryngectomy, some people speak using an electrolarynx which employs an electromechanical actuator to perform the excitatory function of the absent larynx. Drawbacks of conventional electrolarynx designs include the monotonic sound emitted, the need for a free-hand to operate the device, and the difficulty experienced by many laryngectomees in adapting to its use. One improvement to the electrolarynx, which clinicians and users frequently suggest, is the provision of a convenient hands-free control facility. This would allow more natural use of …


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